Tests for Pulsed High Current Heavy Ion Synchrotron Injection with an MP-Tandem Van de Graaff

The new MARK VII high current negative heavy ion source designed by R. Middleton was operated in a pulsed mode to provide 100-200 ¿a negative ion currents in 230 ¿sec square pulses, 10/sec. These pulses, 50-100 times more intense than normal DC beams, were then accelerated by the MP7 Tandem Van de Graaff accelerator while operating at 14 MV. After charge state analysis, the emittance of the pulsed beam was also measured. The very stable accelerator behavior indicated that even higher currents are possible. Values for 16O are: 115 ¿a 16O. injected, 100 MeV 16O6+, 260 ¿a (43.3 p¿a) 1.8 mm.mr and for 32s are: 170 ¿a 32S- injected, 140 MeV 32S9+, 240 ¿a (26.7 p¿a) 0.51 mm.mr. The high intensity and low emittance of these ion beams make them ideal for injection into a synchrotron like the AGS 30 GeV proton accelerator at BNL.